Rotary fluid pump and motor



April 3, 19 28.

E. J. WENDELL ROTARY FLUID PUMP AND MOTOR Filed May 7, 1927 ZzowsizZ br Patented Apr. 3, 1928. I X

' UNITED STATES PATENT OFFICE.

EVERT JANSEN WENDELL, OF WAYNE, PENNSYLVANIA. ASSIGNQR TO. THE HALE FIRE PUMP ('30., INCL, OF CONSHOHOCKEN, PENNSYLVANIA, CORPORATION OF PENNSYLVANIA.

Application filed May 7, 1927. Serial No. 189,536.

This invention relates to improvements in rotary fluid pumps and motors', and more particularly in that class of pump or motor employing vanes in the rotors adapted to bear resiliently against the walls of the pump or motor caslng and against the companion rotor to function as packing preventing losses due to escape of the fluid between the two rotors and betweenthe incli- 'vidual rotors and the walls of the rotor chamber.

The principal object of the invention is to provide a vane which with its novel retaining means will be highly efiicient in op.- eration due to its self-aligning characteristics, strong and durable, and capable of withstanding excessive and complex strains and stresses to which these vanes are subjected in high pressure mechanism.

The invention further resides in certain novel and improved structural details vincluding novel means for releasing the vanes from the retaining means.

In the attached drawings: 7

Figure 1 is a fragmentary sectional view of a rotary pump in which the rotors are equiped with vanes made in accordance with the present invention;

Fig. 2 is a section on the line2-2,Fig. 1, and a Figure 3 is a fragmentary line 3-3, Fig. 2.

Referring to the drawings, the pui'np illustrated therein comprises a casing 1 having intake channels 2, 2 and discharge channels 3, 3 all communicating with a rotor chamber i in which are mounted in well known manner a pair of cooperating rotors 5 and 6. These rotors are mounted upon shafts 7, 7 which are journaled in the casing in the usual manner. The rotors 5 and 6 are of the intermeshing type having teeth or projections 8 which are adapted to enter correspondingly formed recesses in the opposed rotor. The rotors are adapted to rotate in the direction indicated by the arrows, and as the rotors revolve, the fluid is carried between the rotors and the walls of the chamber 4 from the intake side to the discharge side of the casing, also as indicated by the arrows. In this type of pump in order to section on the preserve the efiiciency and the differential pressure between the intake and discharge sides of the pump, it is necessary to have a close fit'not only between the rotors themselves but between the rotors and the walls of the rotor chamber. In orderto preserve this close fit, I have provided inthe ends of the rotor extensions 8 spring-pressed vanes which bear resiliently upon the walls of the casing and upon'the opposing rotor faces, all as clearly illustrated in Fig. 1.

It has been extremely ,diliicult in pumps of this general character or motors of like nature in which the operating pressures are extremely high to provide a retaining means for the packing'vanes which iscapable of withstanding the heavy and complex stresses and strains to'wlnch it is subjected. The vanes in order to function properly must have free radial movement in the rotors, but

must be held with substantial rigidity from axial movement in the rotor. The pressures tending to give the vanes this axial move ment inv the rotors are extremely high and are continually changing indirection, and it is essential that this axial movement be prevented because of-the tendency of the vanes to cut into and groove the plates abutting the ends of the rotors witha resultant damage to the parts and decrease in effi-- eiency of the machine.

In providing a vane-retaining means meeting these requirements, I provide the rotary extensions 8 with radial slots 9 having at thebottom a transverse offset 10, and the vanes 11 are correspondingly formed to it the recesses 9 and with a transverse flange 12 at the bottom which fits behind the shoulder at the outer'end of the groove extension 10 and limits the outward movement of the vane in the slot. Obviously the vane is introduced into the slot from one end of the latter. From the bottom of the slot 11 a cylindrical passage 18 extends radially inwardly, and this passage is adapted for reception of a hollow retaining pin 14.- which is normally heldpressed outwardly bymeans of a spring 15 which occupies the i and are formed to neatly receive the upper ends of the pins 14, as clearly illustrated,

whereby the vanes are retained by the pins against axial movement in the slots in the rotors which they individually occupy. As

illustrated, the vanes 11 and the slots 10 are i so relatively proportioned that the vane is permitted a predetermined amount of axial movement in the slot, the spring 15-, however, acting through the pin 1 5i in obvious manner and to retain the vanes in a maximum projected position in which the outer end of the vane projects appreciably beyond the periphery of the rotor. i

In order to insert the vanes in the slots, it is only necessary to forcethe pins 14 inwardly to a suflicient extent to permit oi the insertion. Itis necessary, however, in order to release the pins from the slots 16,

both in inserting and withdrawing the vanes, to force the pins inwardly to an extent clearing the said slots, and to make this possible I provide in the vanes narrow passages or apertures 17 extending from the outer end of the vane into the slots 16 at points directly above the normal pin position. By inserting a heavy wire or other suitable tool into and through the passage 17, the pins 14 may be depressed sufiiciently to clear the sides of the slots 16 to thereby permit axial movement of the vane in the rotor either for purposes of insertion or withdrawal.

It will be noted that by employing the slots 16 extending transversely of the vanes for reception of the upper ends of the retaining pins 14, the pins do not prevent any transverse movement or rocking of the vanes in the slots which they occupy, whereas they pins 14: which are made amply large to effectually prevent movement of the vanes in the rotors in an axial direction. The

withstand the strains placed upon them therefore interfere in no way with the normal selfadji1sting characteristics of the vane, but are entirely etfective'to prevent the undersirable movements. By making the pin hollow, the length both of the-pin and oi the spring is maintained eta maximum.

I 'clai'm'i 1. A rotor for rotary pumps and motors having a peripheral and longitudinal slot, :1 vane mounted in said slot, and having therein limited movement radially of the rotor, said vane having oninner rate a transverse slot, a pin mounted in the rotor and adapted'toenter the slot to prevent movement of the vane axially of the rotor, and a spring resiliently retaining the pin inthe slot. 'i

2. A rotor for rotary pumps and motors having a peripheral and longitudinal slot, a vane mounted in said slot and having there-1 in limited movement radiallyof the rotor,v said vane having'on its inner face a transverse slot and an opening extending from the outer face of the vaneinto the transverse slot, a pinslidably mounted in the rotor and adapted to enter the slot at the inner endof said opening to prevent movement of the vane axially or the rotor, and aspri ng resiliently projecting'the pin into the slot,

3. A rotor; for rotary pumps and motors having a peripheral and longitudinal slot, a vane mounted in said slotjand having therein limited movement radially ,of the rotor, said vane having on its'inner face a 85 transverse slot, a hollow pin mounted in the rotor and adapted to project into thesaid' transverse slot to prevent movement of the vane axially of the rotor, and a spring extending into the hollow pin and abutting i the rotor to resiliently retain the pin within the slot.

nvnnr JANSEN WENDELL. 

